How did the plugs look? You may need a new coil. Normally, I'd suggest the fuel system, but if your mileage hasn't changed, then the problem isn't with the fuel system, it's that the fuel isn't burning as completely as it was before. That points to either compression or ignition. Since it's still got strong power, that rules out compression. My money is on a problem with the ignition system, probably the coil.
Take care,
-Chris
------------------
Retired Moderator
MustangNet
My site:
Peckerwoods Pit Stop
My teams site:
Jim Porter Racing
RACECAR spelled backwards is RACECAR
HEY !!! Are you ASE Certified ??? If you are, ask me about iATN.